The goal of this study is to understand the nature of Green Tobacco Sickness (GTS) and the social and biologic factors that influence minority farmworkers,risk for this occupational disease. GTS is acute nicotine poisoning following dermal contact with mature tobacco plants. Most U.S. tobacco is harvested by migrant and seasonal farmworkers, who experience disability and loss of work from GTS. Migrant and seasonal farmworkers in the U.S. are almost exclusively minority, primarily Hispanic or African American. The study has 5 specific aims: (1) to estimate the incidence of GTS in seasonal and migrant farmworkers employed in tobacco production in North Carolina; (2) to determine the risk factors for GTS, including physical environmental and social environmental risk factors, as mediated by biological and behavioral factors; (3) to measure the association of tobacco exposure biomarkers with GTS symptoms and with work related exposure to tobacco plants, as modified by GTS risk factors; (4) to understand farmworker and health care providers interpretations of GTS symptomatology, self-care behaviors and barriers to prevention and treatment seeking; and (5) to disseminate findings concerning GTS risk factors to farmworkers and farmworker service providers. The proposed study will be conducted out of 2 federally-funded migrant health clinics serving 4 counties in North Carolina. The research design has 4 major components to be completed over a three year period. First, surveillance in 36 farmworker labor sites in Year 1 will provide interview and salivary cotinine data to estimate GTS incidence and indicate risk factors for GTS symptoms. Second, a clinical case-control comparison of a total of 60 cases and 60 controls from the two clinics in Years 1 and 2 will specify risk factors for severe GTS. Case-control data will include questionnaire and urinary nicotine metabolites. Surveillance and case-control laboratory assays will be completed by the Division of Health Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention. Third, in-depth interviews with farmworkers and health care providers completed in Year 2 will delineate farmworker interpretations of GTS symptomatology, self-care behaviors and barriers to prevention and treatment seeking. Finally, in Year 3, a program that disseminates findings about GTS risk factors directly to farmworkers and those who provide services to the minority occupational group will be conducted.